Add external plugin usage-insights (#3146)

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

.github/plugin/marketplace.json

@@ -2052,6 +2052,31 @@
         "sha": "edfa6465916b5f4b9c6f8ca558b69518621ab810"
       }
     },
+    {
+      "name": "usage-insights",
+      "description": "Inspect current and historical GitHub Copilot token and AI-credit usage with per-agent rollups and in-canvas session drill-down.",
+      "version": "1.0.0",
+      "author": {
+        "name": "David Kaya",
+        "url": "https://github.com/davidkaya"
+      },
+      "repository": "https://github.com/davidkaya/github-copilot-usage-insights",
+      "homepage": "https://github.com/davidkaya/github-copilot-usage-insights",
+      "license": "MIT",
+      "keywords": [
+        "ai-credits",
+        "canvas",
+        "copilot-extension",
+        "session-analytics",
+        "token-usage",
+        "usage-insights"
+      ],
+      "source": {
+        "source": "github",
+        "repo": "davidkaya/github-copilot-usage-insights",
+        "sha": "3b018ccef438d7086c30bd347f0df707689073ee"
+      }
+    },
     {
       "name": "vercel-plugin",
       "description": "Build and deploy web apps and agents. Comprehensive Vercel ecosystem plugin — relational knowledge graph, skills for every major product, specialized agents, and Vercel conventions. Turns any AI agent into a Vercel expert.",